Total synthesis of (±)-stemonamide and (±)-isostemonamide
摘要:
Two different approaches to the alkaloids stemonamide and isostemonamide using N-acyliminium chemistry are described. The approach using an aldol spirocyclization to construct the second contiguous spirocenter was successful. The total synthesis of these products was completed by 1,4-addition of an appropriate side chain, alpha -methylenation by Mannich reaction, double bond isomerization and closure of the azepine ring. (C) 2002 Elsevier Science Ltd. All rights reserved.
Total Synthesis and Structure Confirmation of Elatenyne: Success of Computational Methods for NMR Prediction with Highly Flexible Diastereomers
作者:Bryony S. Dyson、Jonathan W. Burton、Te-ik Sohn、Byungsook Kim、Hoon Bae、Deukjoon Kim
DOI:10.1021/ja304554e
日期:2012.7.18
reported. This work has not only allowed the full structure determination of all of these natural products but also provides excellent supporting evidence for their proposed biogenesis. The total synthesis of elatenyne demonstrates that DFT calculations of (13)C NMR chemical shifts coupled with biosynthetic postulates, comprise a very useful method for distinguishing among large numbers of highly flexible
Development of the Vinylogous Pictet–Spengler Cyclization and Total Synthesis of (±)‐Lundurine A
作者:Aaron Nash、Xiangbing Qi、Pradip Maity、Kyle Owens、Uttam K. Tambar
DOI:10.1002/anie.201803702
日期:2018.6.4
A novel vinylogous Pictet–Spengler cyclization has been developed for the generation of indole‐annulated medium‐sized rings. The method enables the synthesis of tetrahydroazocinoindoles with a fully substituted carbon center, a prevalent structural motif in many biologically active alkaloids. The strategy has been applied to the total synthesis of (±)‐lundurine A.
Total synthesis of antimalarial diterpenoid (+)-kalihinol A, isolated frommarinespongeAcanthella sp., is achieved. This total synthesis involves regioselective alkylation of an epoxide, construction of a tetrahydropyran ring by iodo-etherification, construction of a cis-decalin ring by intramolecular Diels-Alder reaction, isomerization of cis-decalin to trans-decalin, and subsequent functionalization
Organocatalytic Enantioselective Synthesis of 1,4-Dioxanes and Other Oxa-Heterocycles by Oxetane Desymmetrization
作者:Wen Yang、Jianwei Sun
DOI:10.1002/anie.201509888
日期:2016.1.26
A new asymmetric synthesis of chiral 1,4‐dioxanes and other oxa‐heterocycles has been developed by means of organocatalytic enantioselective desymmetrization of oxetanes. This mild process proceeds with exceedingly high efficiency and enantioselectivity to establish the quaternary stereocenters. This method complements the existing, yet limited, strategies for the synthesis of these oxa‐heterocycles
Carbocation catalysed ring closing aldehyde–olefin metathesis
作者:Shengjun Ni、Johan Franzén
DOI:10.1039/c8cc06734a
日期:——
4-Phenylphenyl-diphenylmethylium tetrafluoroborate catalyses a rare high yielding intramolecular aldehyde–olefin metathesis of enals under mild reaction conditions and low catalyst loading.